首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   69016篇
  免费   2972篇
  国内免费   35篇
  2020年   854篇
  2019年   973篇
  2018年   1409篇
  2017年   1430篇
  2016年   1489篇
  2015年   1081篇
  2014年   1284篇
  2013年   5900篇
  2012年   2367篇
  2011年   2446篇
  2010年   1469篇
  2009年   1458篇
  2008年   2046篇
  2007年   1992篇
  2006年   1819篇
  2005年   1512篇
  2004年   1564篇
  2003年   1488篇
  2002年   1424篇
  2001年   2385篇
  2000年   2225篇
  1999年   1659篇
  1998年   764篇
  1997年   666篇
  1996年   718篇
  1995年   655篇
  1994年   641篇
  1993年   633篇
  1992年   1361篇
  1991年   1248篇
  1990年   1248篇
  1989年   1200篇
  1988年   1161篇
  1987年   1077篇
  1986年   1090篇
  1985年   1133篇
  1984年   921篇
  1983年   796篇
  1979年   914篇
  1978年   694篇
  1975年   761篇
  1974年   883篇
  1973年   868篇
  1972年   765篇
  1971年   694篇
  1970年   604篇
  1969年   645篇
  1968年   776篇
  1967年   665篇
  1966年   655篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
251.
252.
253.
254.
255.
The care of the patient with cancer requires the development not only of a medical plan, but an ethical plan as well. This plan should integrate the physician's and the patient's perceptions of medical and ethical propriety. Jewish biomedical ethical principles are based on the teaching of the Old Testament and its various interpretations. In this paper, I discuss how these principles can be used to help guide the physician caring for the patient with cancer. Other ethical systems could be applied in a similar fashion.  相似文献   
256.
257.
Survey respondents may inaccurately report mental health service utilization for motivational and cognitive reasons. There is little evidence on accuracy of self-reports of mental health service use, and this evidence suggests that respondents tend to underreport inpatient utilization. This study addressed the question of self-report accuracy by comparing survey data from a large probability sample to data from computerized records of publicly funded mental health services. Few inaccuracies in self-reporting were detected. However, despite the use of data bases that were unusually appropriate for verifying self-reports, several problems limited the feasibility of validation. Suggestions are offered for increasing the feasibility of validation in future studies.  相似文献   
258.
259.
Processing resources and age differences in working memory   总被引:1,自引:0,他引:1  
This study investigated the performance of young and old subjects on a modified version of the working memory task developed by Baddeley and Hitch (1974). Subjects were required to verify a set of sentences of varying complexity while they repeated aloud zero, two, or four words. The older subjects took longer to verify the sentences, especially when the sentences were grammatically complex, but the effect of concurrent memory load on verification latency was the same in both groups. These results cast doubt on the notion that there is an age-related decline in one general pool of processing resources. They also suggest that older people have greater difficulty with the active processing aspects, rather than with the passive holding aspects, of working memory tasks.  相似文献   
260.
Hindsight bias: An interaction of automatic and motivational factors?   总被引:1,自引:0,他引:1  
If subjects are asked to recollect a former response after having been informed about the correct response, their recollection tends to approach the correct response. This effect has been termedhindsight bias. We studied hindsight bias in an experiment requiring numerical responses to almanac-type questions for physical quantities. We varied (1) the time at which the correct information was provided, (2) the encoding of the original responses by asking/not asking subjects to give a reason for the respective response, and (3) the motivation to recall correctly. We found that hindsight is less biased if reasons are given and if the correct information is provided at an earlier time. Motivation had only interactive effects: (1) With high motivation to recall correctly, the time the correct information was provided had no influence. (2) With reasons given, the variation of motivation showed no effect. These results rule out purely motivational and purely automatic explanations.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号